Note: Descriptions are shown in the official language in which they were submitted.
CA 02827459 2013-09-17
t,
SYSTEM AND METHOD FOR SEPARATING GASEOUS MATERIAL FROM
FORMATION FLUIDS
FIELD
[0001] The present disclosure relates to production of formation fluids,
and, in
particular, separating gaseous material that is entrained within the formation
fluids.
BACKGROUND
[0002] Gas lock is a problem encountered while producing wells, especially
wells with
horizontal portions. Packer-type gas anchors are provided to remedy gas lock.
However,
packer-type gas anchors are relatively expensive. Further, the packers on
packer-type gas
anchors are susceptible to having debris accumulate thereon and, as a result,
becoming
stuck within the wellbore tubular against which it forms a seal. This makes it
difficult to
remove production tubing from the wellbore, such as during a workover. Such
attempt at
removal may also damage the packer, thereby rendering the packer-type gas
anchor
unusable for future production.
SUMMARY
[0003] In one aspect there is provided a system for effecting production
of formation
fluid from a subterranean formation, comprising:
a wellbore tubular disposed within a wellbore, wherein the wellbore tubular
includes a
receptacle portion, wherein the receptacle portion includes a receptacle
sealing surface;
a production tubular, disposed within the wellbore tubular, including:
a formation fluid-receiving conduit portion, defining a formation fluid-
receiving
fluid passage portion for receiving the formation fluid, and including a
sealing member-
engaging surface portion;
DOCSTOR: 2812890\1
CA 02827459 2013-09-17
a gas separator portion configured to co-operate with at least the wellbore
tubular
for effecting separation of at least a fraction of gaseous material, that is
entrained within
the received formation fluid, from the received formation fluid to generate a
gaseous
material-depleted formation fluid;
a gaseous material-depleted fluid formation conduit defining a gaseous
material-
depleted formation fluid conducting-fluid passage portion for conducting a
flow of the
gaseous material-depleted formation fluid to the surface; and
a prime mover disposed for inducing flow of the formation fluid from a
subterranean formation and into the formation fluid-receiving fluid passage
portion, and
for receiving and energizing the gaseous material-depleted formation fluid to
flow through
the gaseous material-depleted formation fluid conducting-fluid passage portion
to the
surface;
and
a sealing member disposed between the sealing member-engaging surface portion
and the
receptacle sealing surface for effecting a seal between at least the sealing
member-
engaging surface portion and the receptacle sealing surface, for preventing,
or substantially
preventing, flow of the formation fluid between at least the sealing member-
engaging
external surface portion and the receptacle sealing surface;
wherein the co-operation between the gas separator portion and at least the
wellbore
tubular is with effect that, while the flow of the formation fluid is being
induced by the
prime mover and received through the formation fluid-receiving fluid passage
portion,
flowing of the received formation fluid is directed through a gas separator
annulus
disposed between the gas separator portion and the wellbore tubular, in a
direction
opposite to that which the formation fluid is flowing while being received by
the formation
fluid-receiving fluid passage portion of the formation fluid-receiving conduit
portion of the
production tubular, prior to being received by the prime mover, and the
formation fluid
flowing through the gas separator annulus is prevented, or substantially
prevented, from
returning to the formation fluid-receiving fluid passage portion of the
formation fluid-
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. %
receiving conduit portion of the production tubular by the effected seal
between at least the
sealing member-engaging surface portion of the formation fluid-receiving
conduit portion
of the production tubular and the receptacle sealing surface of the receptacle
portion of the
wellbore tubular, wherein, while the flowing of the received formation fluid
is being
directed through the gas separator annulus, the at least a fraction of the
entrained gaseous
material becomes separated, in response to buoyancy forces, from the received
formation
fluid that is being directed through the gas separator annulus;
and wherein the receptacle sealing surface is disposed less than a distance
"D" of 2.5
millimetres from the sealing member-engaging surface portion.
[0004] In another aspect there is provided a system for effecting
production of
formation fluids from a subterranean formation, comprising:
a wellbore tubular disposed within a wellbore, wherein the wellbore tubular
includes:
a casing string;
a liner string, coupled to the casing string, the liner string including:
a polished bore receptacle that includes a receptacle portion, wherein the
receptacle portion includes a receptacle sealing surface; and
a sealing surface, sealingly engaged to the casing string for preventing, or
substantially preventing, flow of formation fluid between the sealing surface
and
the casing string; and
a production tubular, disposed within the wellbore tubular, including:
a formation fluid-receiving conduit portion, defining a formation fluid-
receiving
fluid passage portion for receiving the formation fluid, and including a
sealing surface
disposed in sealing engagement with the receptacle sealing surface for
preventing, or
substantially preventing, flow of the formation fluids between the sealing
surface and the
receptacle sealing surface;;
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=
a gas separator portion configured to co-operate with at least the wellbore
tubular
for effecting separation of at least a fraction of gaseous material, that is
entrained within
the received formation fluid, from the received formation fluid to generate a
gaseous
material-depleted formation fluid;
a gaseous material-depleted fluid formation conduit defining a gaseous
material-
depleted formation fluid conducting-fluid passage portion for conducting a
flow of the
gaseous material-depleted formation fluid to the surface; and
a prime mover disposed for inducing flow of the formation fluid from a
subterranean formation and into the formation fluid-receiving fluid passage
portion, and
for receiving and energizing the gaseous material-depleted formation fluid to
flow through
the gaseous material-depleted formation fluid conducting-fluid passage portion
to the
surface;
wherein the co-operation between the gas separator portion and at least the
wellbore
tubular is with effect that, while the flow of the formation fluid is being
induced by the
prime mover and received through the formation fluid-receiving fluid passage
portion,
flowing of the received formation fluid is directed through a gas separator
annulus
disposed between the gas separator portion and the wellbore tubular, in a
direction
opposite to that which the formation fluid is flowing while being received by
the formation
fluid-receiving fluid passage portion of the formation fluid-receiving conduit
portion of the
production tubular, prior to being received by the prime mover, and the
formation fluid
flowing through the gas separator annulus is prevented, or substantially
prevented, from
returning to the formation fluid-receiving fluid passage portion of the
formation fluid-
receiving conduit portion of the production tubular by at least the sealing
engagement
between the sealing surface of the formation fluid-receiving conduit portion
of the
production tubular and the receptacle sealing surface of the receptacle
portion of the
wellbore tubular, wherein, while the flowing of the received formation fluid
is being
directed through the gas separator annulus, the at least a fraction of the
entrained gaseous
material becomes separated, in response to buoyancy forces, from the received
formation
fluid that is being directed through the gas separator annulus.
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= .,
[0005] In
another aspect there is provided a system for effecting production of
formation fluids from a subterranean formation, comprising:
a wellbore tubular disposed within a wellbore, wherein the wellbore tubular
includes a
casing, wherein the casing includes a receptacle portion, wherein the
receptacle portion is
defined by an inwardly extending protrusion of the casing and includes a
receptacle sealing
surface; and
a production tubular, disposed within the wellbore tubular, including:
a formation fluid-receiving conduit portion, defining a formation fluid-
receiving
fluid passage portion for receiving the formation fluid, and including a
sealing surface
disposed in sealing engagement with the receptacle sealing surface for
preventing, or
substantially preventing, flow of the formation fluids between the sealing
surface and the
receptacle sealing surface;
a gas separator portion configured to co-operate with at least the wellbore
tubular
for effecting separation of at least a fraction of gaseous material, that is
entrained within
the received formation fluid, from the received formation fluid to generate a
gaseous
material-depleted formation fluid;
a gaseous material-depleted fluid formation conduit defining a gaseous
material-
depleted formation fluid conducting-fluid passage portion for conducting a
flow of the
gaseous material-depleted formation fluid to the surface; and
a prime mover disposed for inducing flow of the formation fluid from a
subterranean formation and into the formation fluid-receiving fluid passage
portion, and
for receiving and energizing the gaseous material-depleted formation fluid to
flow through
the gaseous material-depleted formation fluid conducting-fluid passage portion
to the
surface;
wherein the co-operation between the gas separator portion and at least the
wellbore
tubular is with effect that, while the flow of the formation fluid is being
induced by the
CA 02827459 2013-09-17
prime mover and received through the formation fluid-receiving fluid passage
portion,
flowing of the received formation fluid is directed through a gas separator
annulus
disposed between the gas separator portion and the wellbore tubular, in a
direction
opposite to that which the formation fluid is flowing while being received by
the formation
fluid-receiving fluid passage portion of the formation fluid-receiving conduit
portion of the
production tubular, prior to being received by the prime mover, and the
formation fluid
flowing through the gas separator annulus is prevented, or substantially
prevented, from
returning to the formation fluid-receiving fluid passage portion of the
formation fluid-
receiving conduit portion of the production tubular by at least the sealing
engagement
between the sealing surface of the formation fluid-receiving conduit portion
of the
production tubular and the receptacle sealing surface of the receptacle
portion of the
wellbore tubular, wherein, while the flowing of the received formation fluid
is being
directed through the gas separator annulus, the at least a fraction of the
entrained gaseous
material becomes separated, in response to buoyancy forces, from the received
formation
fluid that is being directed through the gas separator annulus.
[0006] In
another aspect there is provided a process for effecting production of
formation fluids from a subterranean formation, comprising:
positioning a wellbore tubular within a wellbore, wherein the wellbore tubular
includes a
receptacle portion, wherein the receptacle portion includes a receptacle
sealing surface;
providing a production tubular, wherein the production tubular includes:
a formation fluid-receiving conduit portion, defining a formation fluid-
receiving
fluid passage portion for receiving the formation fluid, and including a
sealing member-
engaging surface portion;
a gas separator portion;
a gaseous material-depleted fluid formation conduit defining a gaseous
material-
depleted formation fluid conducting-fluid passage portion for conducting a
flow of the
gaseous material-depleted formation fluid to the surface; and
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a prime mover disposed for inducing flow of the formation fluid from a
subterranean formation and into the formation fluid-receiving fluid passage
portion, and
for receiving and energizing the gaseous material-depleted formation fluid to
flow through
the gaseous material-depleted formation fluid conducting-fluid passage portion
to the
surface;
and
a sealing member disposable between the sealing member-engaging surface
portion and
the receptacle sealing surface for effecting a seal between at least the
sealing member-
engaging surface portion and the receptacle sealing surface, for preventing,
or substantially
preventing, flow of the formation fluid between at least the sealing member-
engaging
surface portion and the receptacle sealing surface;
wherein, while the production tubular is positioned within the wellbore
tubular such that
the seal between at least the sealing member-engaging surface portion and the
receptacle
sealing surface is being effected, the gas separator portion is configured to
co-operate with
at least the wellbore tubular for effecting separation of at least a fraction
of gaseous
material, that is entrained within the received formation fluid, from the
received formation
fluid to generate a gaseous material-depleted formation fluid;
and wherein the co-operation between the gas separator portion and at least
the wellbore
tubular is with effect that, while the flow of the formation fluid is being
induced by the
prime mover and received through the formation fluid-receiving fluid passage
portion,
flowing of the received formation fluid is directed through a gas separator
annulus
disposed between the gas separator portion and the wellbore tubular, in a
direction
opposite to that which the formation fluid is flowing while being received by
the formation
fluid-receiving fluid passage portion of the formation fluid-receiving conduit
portion of the
production tubular, prior to being received by the prime mover, and the
formation fluid
flowing through the gas separator annulus is prevented, or substantially
prevented, from
returning to the formation fluid-receiving fluid passage portion of the
formation fluid-
receiving conduit portion of the production tubular by the effected seal
between at least the
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sealing member-engaging surface portion of the formation fluid-receiving
conduit portion
of the production tubular and the receptacle sealing surface of the receptacle
portion of the
wellbore tubular, wherein, while the flowing of the received formation fluid
is being
directed through the gas separator annulus, the at least a fraction of the
entrained gaseous
material becomes separated, in response to buoyancy forces, from the received
formation
fluid that is being directed through the gas separator annulus, and the
receptacle sealing
surface is disposed less than a distance "D" of 2.5 millimetres from the
sealing member-
engaging surface portion.
positioning the production tubular within the wellbore tubular such that the
seal between at
least the sealing member-engaging surface portion and the receptacle sealing
surface is
being effected;
inducing flow of the formation fluid, from a treated subterranean formation to
the
formation fluid-receiving fluid passage portion of the formation fluid-
receiving conduit
portion of the production tubular, by the prime mover;
directing flow of the received formation fluid through the gas separator
annulus, in a
direction opposite to that which the formation fluid is flowing while being
received by the
formation fluid-receiving fluid passage portion of the formation fluid-
receiving conduit
portion of the production tubular, by the co-operating of the gas separator
with the
wellbore tubular;
preventing, or substantially preventing, the received formation fluid, that is
flowing
through the gas separator annulus, from returning to the formation fluid-
receiving fluid
passage portion of the formation fluid-receiving conduit portion of the
production tubular
by the seal effected between at least the seal member-engaging sealing surface
portion of
the formation fluid-receiving conduit portion of the production tubular and
the receptacle
sealing surface of the receptacle portion of the wellbore tubular;
while the flow of the received formation fluid is being directed through the
gas separator
annulus, effecting separation, in response to buoyancy forces, of at least a
fraction of
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gaseous material entrained within the formation fluid flow being flowed
through the gas
separator annulus to generate a gaseous material-depleted formation fluid
flow;
energizing the gaseous material-depleted formation fluid flow with the prime
mover for
flow to the surface through the gaseous material-depleted fluid formation
conduit of the
production tubular; and
conducting the energized gaseous material-depleted formation fluid flow to the
surface
through the gaseous material-depleted fluid formation conduit of the
production tubular.
[0007] In
another aspect there is provided a process for effecting production of
formation fluids from a subterranean formation, comprising:
positioning a wellbore tubular within a wellbore, wherein the wellbore tubular
includes:
a casing string;
a liner string, coupled to the casing string, the liner string including:
a polished bore receptacle that includes a receptacle portion, wherein the
receptacle portion includes a receptacle sealing surface; and
a sealing surface, sealingly engaged to the casing string for preventing, or
substantially preventing, flow of formation fluid between the sealing surface
and
the casing string;
providing a production tubular, wherein the production tubular includes:
a formation fluid-receiving conduit portion, defining a formation fluid-
receiving
fluid passage portion for receiving the formation fluid, and including a
sealing surface
disposable for sealing engagement with the receptacle sealing surface for
preventing, or
substantially preventing, flow of the formation fluids between the sealing
surface and the
receptacle sealing surface;
a gas separator portion;
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a gaseous material-depleted fluid formation conduit defining a gaseous
material-
depleted formation fluid conducting-fluid passage portion for conducting a
flow of the
gaseous material-depleted formation fluid to the surface; and
a prime mover disposed for inducing flow of the formation fluid from a
subterranean formation and into the formation fluid-receiving fluid passage
portion, and
for receiving and energizing the gaseous material-depleted formation fluid to
flow through
the gaseous material-depleted formation fluid conducting-fluid passage portion
to the
surface;
wherein, while the production tubular is positioned within the wellbore
tubular such that
the sealing engagement between at least the sealing surface of the formation
fluid-
receiving conduit portion and the receptacle sealing surface of the receptacle
portion is
being effected, the gas separator portion is configured to co-operate with at
least the
wellbore tubular for effecting separation of at least a fraction of gaseous
material, that is
entrained within the received formation fluid, from the received formation
fluid to generate
a gaseous material-depleted formation fluid;
and wherein the co-operation between the gas separator portion and at least
the wellbore
tubular is with effect that, while the flow of the formation fluid is being
induced by the
prime mover and received through the formation fluid-receiving fluid passage
portion,
flowing of the received formation fluid is directed through a gas separator
annulus
disposed between the gas separator portion and the wellbore tubular, in a
direction
opposite to that which the formation fluid is flowing while being received by
the formation
fluid-receiving fluid passage portion of the formation fluid-receiving conduit
portion of the
production tubular, prior to being received by the prime mover, and the
formation fluid
flowing through the gas separator annulus is prevented, or substantially
prevented, from
returning to the formation fluid-receiving fluid passage portion of the
formation fluid-
receiving conduit portion of the production tubular by the sealing engagement
between at
least the sealing surface of the formation fluid-receiving conduit portion of
the production
tubular and the receptacle sealing surface of the receptacle portion of the
wellbore tubular,
wherein, while the flowing of the received formation fluid is being directed
through the gas
CA 02827459 2013-09-17
separator annulus, the at least a fraction of the entrained gaseous material
becomes
separated, in response to buoyancy forces, from the received formation fluid
that is being
directed through the gas separator annulus;
positioning the production tubular within the wellbore tubular such that the
sealing
engagement between at least the sealing surface of the formation fluid-
receiving conduit
portion of the production tubular and the receptacle sealing surface of the
receptacle
portion of the wellbore tubular is being effected;
inducing flow of the formation fluid, from a treated subterranean formation to
the
formation fluid-receiving fluid passage portion of the formation fluid-
receiving conduit
portion of the production tubular, by the prime mover;
directing flow of the received formation fluid through the gas separator
annulus, in a
direction opposite to that which the formation fluid is flowing while being
received by the
formation fluid-receiving fluid passage portion of the formation fluid-
receiving conduit
portion of the production tubular, by the co-operating of the gas separator
with the
wellbore tubular;
preventing, or substantially preventing, the received formation fluid, that is
flowing
through the gas separator annulus, from returning to the formation fluid-
receiving fluid
passage portion of the formation fluid-receiving conduit portion of the
production tubular
by the sealing engagement between at least the sealing surface of the
formation fluid-
receiving conduit portion of the production tubular and the receptacle portion
of the
wellbore tubular;
while the flow of the received formation fluid is being directed through the
gas separator
annulus, effecting separation, in response to buoyancy forces, of at least a
fraction of
gaseous material entrained within the formation fluid flow being flowed
through the gas
separator annulus to generate a gaseous material-depleted formation fluid
flow;
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energizing the gaseous material-depleted formation fluid flow with the prime
mover for
flow to the surface through the gaseous material-depleted fluid formation
conduit of the
production tubular; and
conducting the energized gaseous material-depleted formation fluid flow to the
surface
through the gaseous material-depleted fluid formation conduit of the
production tubular.
[0008] In
another aspect there is provided a process for effecting production of
formation fluids from a subterranean formation, comprising:
positioning a wellbore tubular within a wellbore, wherein the wellbore tubular
includes a
casing, wherein the casing includes a receptacle portion, wherein the
receptacle portion is
defined by an inwardly extending protrusion of the casing and includes a
receptacle sealing
surface;
providing a production tubular, wherein the production tubular includes:
a formation fluid-receiving conduit portion, defining a formation fluid-
receiving
fluid passage portion for receiving the formation fluid, and including a
sealing surface
disposable for sealing engagement with the receptacle sealing surface for
preventing, or
substantially preventing, flow of the formation fluids between the sealing
surface and the
receptacle sealing surface;
a gas separator portion;
a gaseous material-depleted fluid formation conduit defining a gaseous
material-
depleted formation fluid conducting-fluid passage portion for conducting a
flow of the
gaseous material-depleted formation fluid to the surface; and
a prime mover disposed for inducing flow of the formation fluid from a
subterranean formation and into the formation fluid-receiving fluid passage
portion, and
for receiving and energizing the gaseous material-depleted formation fluid to
flow through
the gaseous material-depleted formation fluid conducting-fluid passage portion
to the
surface;
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wherein, while the production tubular is positioned within the wellbore
tubular such that
the sealing engagement between at least the sealing surface of the formation
fluid-
receiving conduit portion and the receptacle sealing surface of the receptacle
portion is
being effected, the gas separator portion is configured to co-operate with at
least the
wellbore tubular for effecting separation of at least a fraction of gaseous
material, that is
entrained within the received formation fluid, from the received formation
fluid to generate
a gaseous material-depleted formation fluid;
and wherein the co-operation between the gas separator portion and at least
the wellbore
tubular is with effect that, while the flow of the formation fluid is being
induced by the
prime mover and received through the formation fluid-receiving fluid passage
portion,
flowing of the received formation fluid is directed through a gas separator
annulus
disposed between the gas separator portion and the wellbore tubular, in a
direction
opposite to that which the formation fluid is flowing while being received by
the formation
fluid-receiving fluid passage portion of the formation fluid-receiving conduit
portion of the
production tubular, prior to being received by the prime mover, and the
formation fluid
flowing through the gas separator annulus is prevented, or substantially
prevented, from
returning to the formation fluid-receiving fluid passage portion of the
formation fluid-
receiving conduit portion of the production tubular by the sealing engagement
between at
least the sealing surface of the formation fluid-receiving conduit portion of
the production
tubular and the receptacle sealing surface of the receptacle portion of the
wellbore tubular,
wherein, while the flowing of the received formation fluid is being directed
through the gas
separator annulus, the at least a fraction of the entrained gaseous material
becomes
separated, in response to buoyancy forces, from the received formation fluid
that is being
directed through the gas separator annulus;
positioning the production tubular within the wellbore tubular such that the
sealing
engagement between at least the sealing surface of the formation fluid-
receiving conduit
portion of the production tubular and the receptacle sealing surface of the
receptacle
portion of the wellbore tubular is being effected;
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inducing flow of the formation fluid, from a treated subterranean formation to
the
formation fluid-receiving fluid passage portion of the formation fluid-
receiving conduit
portion of the production tubular, by the prime mover;
directing flow of the received formation fluid through the gas separator
annulus, in a
direction opposite to that which the formation fluid is flowing while being
received by the
formation fluid-receiving fluid passage portion of the formation fluid-
receiving conduit
portion of the production tubular, by the co-operating of the gas separator
with the
wellbore tubular;
preventing, or substantially preventing, the received formation fluid, that is
flowing
through the gas separator annulus, from returning to the formation fluid-
receiving fluid
passage portion of the formation fluid-receiving conduit portion of the
production tubular
by the sealing engagement between at least the sealing surface of the
formation fluid-
receiving conduit portion of the production tubular and the receptacle portion
of the
wellbore tubular;
while the flow of the received formation fluid is being directed through the
gas separator
annulus, effecting separation, in response to buoyancy forces, of at least a
fraction of
gaseous material entrained within the formation fluid flow being flowed
through the gas
separator annulus to generate a gaseous material-depleted formation fluid
flow;
energizing the gaseous material-depleted formation fluid flow with the prime
mover for
flow to the surface through the gaseous material-depleted fluid formation
conduit of the
production tubular; and
conducting the energized gaseous material-depleted formation fluid flow to the
surface
through the gaseous material-depleted fluid formation conduit of the
production tubular.
BRIEF DESCRIPTION OF DRAWINGS
100091 The
preferred embodiments will now be described with the following
accompanying drawings, in which:
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=
[0010] Figure 1 is a schematic illustration of an embodiment of the present
disclosure,
illustrating fluid flowpath through the gas separator;
[0011] Figure 2 is a schematic illustration of an enlarged portion of the
embodiment
illustrated in Figure 1, in the region of the gas separator;
[0012] Figure 2A is a schematic illustration of a further enlarged portion
of the
embodiment illustrated in Figure 1, in the region of the gas separator, and
specifically
illustrating the relative spatial disposition between a receptacle sealing
surface of the
wellbore tubular and the sealing member-engaging surface portion of the
production
tubular;
[0013] Figure 3 is a schematic illustration of another embodiment of the
present
disclosure, also illustrating fluid flowpath through the gas separator; and
[0014] Figure 4 is a schematic illustration of an enlarged portion of the
embodiment
illustrated in Figure 1, in the region of the gas separator.
DETAILED DESCRIPTION
[0015] The term "upwardly" means, in a spatial context, from a lower
position to an
upper position. The lower and upper positions do not necessarily need to be in
perfect
vertical alignment, but this possibility is not excluded.
[0016] The term "downardly" means, in a spatial context, from an upper
position to a
lower position. The upper and lower position do not necessarily need to be in
perfect
vertical alignment, but this possibility is not excluded.
[0017] The term "tubular" refers to any generally tubular conduit (not
necessarily
cylindrical in cross-section) for transporting fluid, into or from a
subterranean formation. A
"tubular", as deployed in a wellbore, may be formed from individual, discrete
lengths of
generally tubular conduit that are joined together to form, for example a
tubing string, drill
string, casing string, or liner. In this respect, a tubular may be a tubing
string, drill string,
casing string, or liner. Any of these structures are positioned within a
wellbore and
CA 02827459 2013-09-17
utilized, at least in part, to transport fluids. The tubular may have a bore
of a generally
uniform diameter throughout the length thereof or may have two or more
sections having
bores of different diameters. In some embodiments, for example, one or more
downhole
tools may be secured to the tubular.
[0018] "Formation fluid" is fluid that is contained within a subterranean
formation.
Formation fluid may be liquid material, gaseous material, or a mixture of
liquid material
and gaseous material. In some embodiments, for example, the formation fluid
includes
hydrocarbonaceous material, such as oil, natural gas, or combinations thereof.
[0019] Referring to Figures 1 to 4, there is provided a system 10 for
effecting
production of formation fluids from a subterranean formation 50. The system
includes a
wellbore tubular 20 and a production tubular 30. The wellbore tubular 20 and
the
production tubular 30 extend from a wellhead 15 that is supported on the
ground surface
16.
[0020] The wellbore tubular 20 is disposed or positioned within a wellbore
40. The
wellbore tubular 20 includes a receptacle portion 22. The receptacle portion
22 includes a
receptacle sealing surface 21.
[0021] The wellbore 40 can be straight, curved, or branched. The wellbore
can have
various wellbore portions. A wellbore portion is an axial length of a
wellbore. A wellbore
portion can be characterized as "vertical" or "horizontal" even though the
actual axial
orientation can vary from true vertical or true horizontal, and even though
the axial path
can tend to "corkscrew" or otherwise vary. The term "horizontal", when used to
describe a
wellbore portion, refers to a horizontal or highly deviated wellbore portion
as understood
in the art, such as, for example, a wellbore portion having a longitudinal
axis that is
between 70 and 110 degrees from vertical.
[0022] In some embodiments, for example, the wellbore tubular 20 includes a
casing.
The casing isolates certain zones of the subterranean formation 50 from the
formation fluid
being produced from another zone of the subterranean formation. In some
embodiments,
for example, the casing stabilizes the subterranean formation during drilling
of the
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wellbore, as well as after the wellbore has been completed, by preventing the
collapse of
the subterranean formation that is defining the wellbore.
[0023] In some embodiments, for example, the casing 20 includes one or more
casing
strings, each of which is positioned within the well bore, having one end
extending from
the well head, either surface or subsea. The casing strings may be cemented to
the
wellbore. The combination of cement and casing strengthens the wellbore and
facilitates
the isolation of certain areas of the subterranean formation behind the casing
for the
production of formation fluids. In some embodiments, for example and referring
to Figure
1, the casing, including one or more casing strings, is connected at its other
end to a liner
string 26. The liner string extends only a short distance above the lower end
of the
previously installed casing string and is suspended within the wellbore by a
liner hanger
connected to the previously installed casing string. The liner string can be
made from the
same material as the casing string, but, unlike the casing string, the liner
string does not
extend back to the wellhead. The liner string may be cemented to the wellbore,
or remain
uncemented.
100241 In some embodiments, for example and referring to Figures 3 and 4,
the casing
may include one or more expandable liner strings. During assembly of the
casing, and
after being disposed in the wellbore, the expandable liner string is expanded
diametrically
into frictional engagement with the previous string of casing or liner (which
could also
have been expanded diametrically into frictional engagement with a further
previous string
of casing or liner). The expanded string may be cemented to the wellbore, or
remain
uncemented. The assembly of the casing, using such expandable liner strings,
effects
production of at least a casing section generally described as a "monobore"
casing or
casing section.
100251 In some embodiments, for example, the production tubular may be a
tubular
string that includes several "joints" (a "joint" is a length of pipe) or other
tubular members
assembled to create the string.
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CA 02827459 2013-09-17
[0026] The production tubular 30 is disposed within the wellbore tubular
20. The
production tubular includes a formation fluid-receiving conduit portion 32, a
gas separator
portion 38, a gaseous material-depleted fluid formation conduit portion 34,
and a prime
mover 36.
[0027] The formation fluid-receiving conduit portion 32 includes a
formation fluid-
receiving fluid passage-defining surface 323 that defines a formation fluid-
receiving fluid
passage portion 3231 for receiving the formation fluid.
[0028] In one aspect, the formation fluid-receiving conduit portion
includes a sealing
surface 321 disposed in sealing engagement with the receptacle sealing surface
21 for
preventing, or substantially preventing, flow of the formation fluids between
the sealing
surface 321 and the receptacle sealing surface 21. The sealing engagement
effects a seal
between the sealing surface 321 and the receptacle sealing surface 21. In some
embodiments, for example, one of the sealing surfaces 21 or 321 is defined by
a sealing
member 400 that is disposed between the formation fluid-receiving conduit
portion 32 and
the receptacle portion 22 for effecting the seal between the formation fluid-
receiving
conduit portion 32 and the receptacle portion 22.
[0029] In some embodiments, for example, the sealing member 400 includes
resilient
material, such as elastomeric material. In some embodiments, for example, the
sealing
member 400 includes deformable metallic materials.
[0030] The gas separator portion 38 is configured to co-operate with at
least the
wellbore tubular 20 for effecting separation of at least a fraction of gaseous
material, that is
entrained within the received formation fluid, from the received formation
fluid to generate
a gaseous material-depleted formation fluid.
[0031] The gaseous material-depleted fluid formation conduit portion 34
defines a
gaseous material-depleted formation fluid conducting-fluid passage portion 341
for
conducting a flow of the gaseous material-depleted formation fluid to the
surface.
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CA 02827459 2013-09-17
[0032] The prime mover 36 is disposed for inducing flow of the formation
fluid from a
subterranean formation and into the formation fluid-receiving fluid passage
portion 3231,
and for receiving and energizing the gaseous material-depleted formation fluid
to flow
through the gaseous material-depleted formation fluid conducting-fluid passage
portion
341 to the surface. In some embodiments, for example, the prime mover 36 is a
fluid
propeller. In some of these embodiments, for example, the prime mover is a
pump, such as
a downhole pump. In some embodiments, for example, the pump is a rod pump,
such as a
sucker rod pump.
[00331 The co-operation between the gas separator portion 38 and at least
the wellbore
tubular 20 is with effect that, while the flow of the formation fluid is being
induced by the
prime mover 36 and received through the formation fluid-receiving fluid
passage portion
3231, flowing of the received formation fluid is directed through a gas
separator annulus
381 disposed between the gas separator portion 38 and the wellbore tubular 20,
in a
direction opposite to that which the formation fluid is flowing while being
received by the
formation fluid-receiving fluid passage portion 3231 of the formation fluid-
receiving
conduit portion 32 of the production tubular 30, prior to being received by
the prime mover
36, and the formation fluid flowing through the gas separator annulus 381 is
prevented, or
substantially prevented, from returning to the formation fluid-receiving fluid
passage
portion 3231 of the formation fluid-receiving conduit portion 32 of the
production tubular
30 by at least the seal formed (as above-described) between the formation
fluid-receiving
conduit portion 32 of the production tubular 30 and the receptacle portion 22
of the
wellbore tubular 20, wherein, while the flowing of the received formation
fluid is being
directed through the gas separator annulus 381, the at least a fraction of the
entrained
gaseous material becomes separated, in response to buoyancy forces, from the
received
formation fluid that is being directed through the gas separator annulus 381.
[0034] Referring to Figure 2A, in another aspect, the formation fluid-
receiving conduit
portion 32 includes a sealing member-engaging surface portion 325, and a
sealing member
400 is disposed between a sealing member-engaging surface portion 325 of the
formation
fluid-receiving conduit portion 32 and the receptacle sealing surface 21 for
effecting the
19
CA 02827459 2013-09-17
seal between at least the sealing member-engaging surface portion 325 and the
receptacle
sealing surface 21, for preventing, or substantially preventing, flow of the
formation fluid
between at least the sealing member-engaging surface portion 325 and the
receptacle
sealing surface 21. In some of these embodiments, for example, the sealing
member 400 is
coupled to, or carried, by the formation fluid-receiving conduit portion 32.
The receptacle
sealing surface 21 is disposed less than a distance "D" of 2.5 millimetres
from the sealing
member-engaging surface portion 325. In some embodiments, for example, the
distance
"D" is one (1) millimetre, such that the receptacle sealing surface 21 is
disposed less than
one (1) millimetre from the sealing member-engaging surface portion 325 . This
distance
"D" is selected so as to minimize debris accumulation but still permit the in
installation of
the sealing member 400.
[0035] By
effecting separation of at least a fraction of gaseous material, that is
entrained within the received flow of formation fluid, from the received
formation fluid,
the gas lock phenomena is at least partially mitigated by the co-operation of
the gas
separator 38 and the wellbore tubular 20. Unlike existing packer-type gas
anchors, by co-
operatively configuring the wellbore tubular 20 and the production tubular 30
such that the
provided spacing between the receptacle sealing surface 21, of the wellbore
tubular 20, and
the sealing member-engaging surface portion 325, of the production tubular 30,
is below a
predetermined distance (as defined above), the amount of space to be dedicated
for
effecting the sealing engagement between the receptacle sealing surface 21 and
the sealing
member-engaging surface portion 325 can be minimized such that conventional
packers
are not required to be used associated with the gas separator portion 38 to
effect the
necessary sealing for preventing, or substantially preventing flow between the
tubulars 20,
30 in order for the removal of the entrained gases to be effected. Because
this is the case,
the problem of debris accumulation on the packer, which would otherwise make
it more
difficult to remove the production tubular 30, from the wellbore tubular 20,
owing to the
fact that such accumulated debris may cause the packer associated with a gas
separator,
disposed on the production tubular 30, to be stuck against the wellbore
tubular 20, is
eliminated or mitigated, at least as it relates to its relevance to
removability of the
production tubular 30 from the wellbore, such as during workovers.
CA 02827459 2013-09-17
[0036] In some embodiments, for example, the production tubular 30 is
releasably
secured to the wellbore tubular 20. In some of these embodiments, for example,
the
production tubular is disposed in an interference fit relationship (such as a
press-fit
relationship) with the wellbore tubular 20. In some of these embodiments, for
example,
the interference fit relationship is effected between the sealing surface 321
of the formation
fluid-receiving conduit portion 32 of the production tubular 30 and the
receptacle sealing
surface 21 of the receptacle portion 22 of the wellbore tubular 20.
[0037] Referring to Figures 1 and 2, in some embodiments, for example, the
wellbore
tubular 20 includes a casing 2, and the casing includes a casing string 201
and a liner string
26. In some embodiments, for example, the liner string 26 is hung from the
casing string
201. The liner string 26 includes a polished bore receptacle 261 and an
external sealing
surface 262. The polished bore receptacle 261 includes the receptacle portion
22. The
external sealing surface 262 is sealingly engaged to the casing string 201 for
preventing, or
substantially preventing, flow of formation fluid between the external sealing
surface 262
and the casing string 201. In some embodiments, for example, the sealing
engagement
between the surface 262 and the casing string 201 is effected by a packer 24
mounted to
the casing string 201. The production tubular 30 is disposed within the
polished bore
receptacle 261, and urging of the sealing engagement between the sealing
surface 321 of
the production tubular 30 and the receptacle sealing surface 21 of the
receptacle portion 22
of the polished bore receptacle 261 is effected with a seal latch assembly
that releasably
secures the production tubular 30 to the polished bore receptacle 261. In some
embodiments, for example, the production tubular 30 is releasably coupled or
releasably
secured to the polished bore receptacle 261. In some of these embodiments, for
example,
the releasable coupling (or the releasable securement) is effected by way of
an interference
fit engagement (such as a press-fit engagement) between the production tubular
30 and the
receptacle portion 22 of the polished bore receptacle 261.
[0038] Referring to Figures 3 and 4, in some embodiments, for example, the
wellbore
tubular 20 includes a casing 2, and the receptacle portion 22 extends inwardly
from the
casing 2. In some embodiments, for example, the receptacle portion 22 defines
a
21
CA 02827459 2013-09-17
constricted portion 221 of the casing 2. In some embodiments, for example, the
production
tubular 30 is releasably coupled or releasably secured to the receptacle
portion 22. In some
of these embodiments, for example, the releasable coupling (or the releasable
securement)
is effected by way of an interference fit engagement (such as a press-fit
engagement)
between the production tubular 30 and the receptacle portion 22. In this
respect, the
extending inward receptacle portion 22 is permanently affixed to the casing 2,
thus any
accumulation of debris will not prevent removal of the production tubular 30
and the
sealing member-engaging surface portion 325.
[0039] In some embodiments, for example, the system further includes a
conducting
annulus 382 disposed between the production tubular 30 and the wellbore
tubular 20. The
conducting annulus 382 is configured to receive and conduct the separated
gaseous
material to the surface. The gas separator annulus 381 is disposed in vertical
alignment
with the conducting annulus 382.
[0040] In some embodiments, for example, the gas separator 38 further co-
operates
with the wellbore tubular 20 with effect that the received formation fluid
flow being
flowed through the gas separator annulus 381 is flowing in a downwardly
direction.
[0041] In some embodiments, for example, the disposition of the wellbore
tubular 20
relative to the wellbore is with effect that the effected fluid communication
between the
formation fluid-receiving fluid passage portion 3231 of the production tubular
30 and the
subterranean formation treatment zone is isolated, or substantially isolated,
from at least
one other zone of the subterranean formation (such as, in Figure 1, by another
packer 501).
[0042] In some embodiments, for example, the prime mover 36 is disposed
within a
horizontal wellbore portion of the wellbore 40.
[0043] In some embodiments, for example, a mechanical filter 327 (such as a
sand
screen) is disposed within the production tubular 30, upstream of the gas
separator 38 for
filtering solids from the formation fluid whose flow has been induced into the
formation
fluid-receiving conduit portion 32. Intermittently, the solids, retained by
the mechanical
filter 327 can be purged by pumping a fluid downhole through the annulus 382.
22
CA 02827459 2013-09-17
100441 In some of these embodiments, for example, a check valve may be
disposed
within the production tubular, upstream of the inlet, for enabling fluid
circulation of a
purging fluid that may be used for cleaning out debris within the production
tubular, while
preventing fluid communication with the production zone.
[0045] There is also provided a process for effecting production of
formation fluids
from a subterranean formation.
[0046] The process includes positioning the wellbore tubular 20 within the
wellbore,
and then positioning the production tubular 30 within the wellbore tubular 20.
[0047] Flow of the formation fluid, from a treated subterranean formation
50 to the
formation fluid-receiving conduit portion 32 of the production tubular 30, is
then induced
by the prime mover 36. The flow of the received formation fluid is directed
through the
gas separator annulus 381, in a direction opposite to that which the formation
fluid is
flowing while being received by the formation fluid-receiving fluid passage
portion 3231
of the production tubular 30, by the co-operating of the gas separator 38 with
the wellbore
tubular 20. The received formation fluid, that is flowing through the gas
separator annulus
381, is prevented, or substantially prevented, from returning to the formation
fluid-
receiving fluid passage portion 3231 of the production tubular 30 by at least
the sealing
engagement between the formation fluid-receiving fluid passage portion 3231 of
the
formation fluid-receiving conduit portion 32 of the production tubular 30 and
the
receptacle sealing surface 21 of the receptacle portion 22 of the wellbore
tubular 20. While
the flow of the received formation fluid is being directed through the gas
separator annulus
381, separation, of at least a fraction of gaseous material entrained within
the formation
fluid flow being flowed through the gas separator annulus 381, in response to
buoyancy
forces, is effected to generate a gaseous material-depleted formation fluid
flow. The
gaseous material-depleted formation fluid flow is energized with the prime
mover 36 for
flow to the surface through the gaseous material-depleted formation fluid
conducting-fluid
passage portion 341 of the production tubular 30. The energized gaseous
material-depleted
formation fluid flow is conducted to the surface through the gaseous material-
depleted
formation fluid conducting-fluid passage portion 341.
23
CA 02827459 2013-09-17
[0048] In some embodiments, for example, the received formation fluid flow,
being
flowed through the gas separator annulus 381, is flowing in a downwardly
direction.
[0049] In some embodiments, for example, while the flow of the formation
fluid, for
receiving by the formation fluid-receiving fluid passage portion 3231 of the
production
tubular 30, is being induced, the formation fluid is flowing in an upwardly
direction.
[0050] In some embodiments, for example, the inducing flow of formation
fluid
includes effecting the development of a sufficient pressure differential,
between the suction
of the prime mover 36 and the subterranean formation 50, by the prime mover
36.
[0051] In some embodiments, for example, the positioning of the production
tubular 30
includes positioning the prime mover 36 within a horizontal wellbore portion
of the
wellbore 40.
[0052] In some embodiments, for example, the process further includes
flowing the
separated gaseous material to the surface through a conducting annulus 382
disposed
between the production tubular 30 and the wellbore tubular 20. In some of
these
embodiments, for example, the gas separator annulus 381 is disposed in
vertical alignment
with the conducting annulus 382. In some of these embodiments, for example,
the flowing
of the separated gaseous material is in a direction opposite to that of the
flow of the
received formation fluid through the gas separator annulus 381.
[0053] In some embodiments, for example, the process further includes,
prior to the
positioning of a production tubular 30 within the wellbore tubular 20, the
steps of:
delivering a wellbore treatment fluid to a treatment zone of the subterranean
formation 50
to effect treatment of the subterranean formation treatment zone, and then
suspending the
delivering of the wellbore treatment fluid. The formation fluid is derived
from the
subterranean formation treatment zone. In some of these embodiments, the
process further
includes, prior to the delivering of the wellbore treatment fluid to the
subterranean
formation treatment zone, the step of positioning the wellbore treatment
tubular into fluid
communication with the subterranean formation treatment zone with effect that
the
wellbore treatment tubular is disposed for conducting wellbore treatment fluid
to the
24
CA 02827459 2013-09-17
subterranean formation treatment zone, and also further includes, after the
delivering of the
wellbore treatment fluid, repositioning the wellbore treatment tubular with
effect that fluid
communication between the wellbore treatment tubular and the receptacle
portion becomes
suspended. After the repositioning, the production tubular 30 is positioned
within the
wellbore tubular 20.
[0054] "Wellbore treatment fluid" refers to fluid used in treatment (such
as
stimulation) of a subterranean formation. Stimulation is a type of treatment
performed on
a subterranean formation to restore or enhance the productivity of oil or gas
or other fluid
within the subterranean formation. Stimulation includes hydraulic fracturing.
Nonlimiting
examples of a suitable wellbore servicing fluid include but are not limited to
a fracturing
fluid, a perforating or hydrajetting fluid, an acidizing fluid, or
combinations thereof.
[0055] In some embodiments, for example, while the delivering of the
wellbore
treatment fluid is being effected, the receptacle 22 is sealingly engaging the
wellbore
treatment tubular.
[0056] The wellbore treatment tubular includes a fluid passage for
conducting wellbore
treatment fluid from a wellbore treatment fluid supply source disposed on the
surface to
the subterranean formation 50. In some embodiments, for example, The wellbore
treatment tubular may be a tubular string that includes several "joints" (a
"joint" is a length
of pipe) or other tubular members assembled to create the string. In some
embodiments,
for example, the wellbore treatment tubular includes one or more downhole
tools for
effecting fracturing of the subterranean formation with which the one or more
downhole
tools is disposed in fracture-effecting communication with when disposed
within the
wellbore.
[0057] One or more flow control devices may be provided for selectively
effecting
fluid communication between the receptacle portion and a subterranean
formation. In
some modes of operation, the effecting of fluid communication between the
wellbore
treatment tubular and a treatment zone of a subterranean formation 50, by the
one or more
flow control valves, provides a flowpath for the delivery of wellbore
treatment fluid. In
CA 02827459 2013-09-17
other modes of operation, the effecting of fluid communication between the
formation
fluid-receiving fluid passage portion 3231 of the production tubular 30 and a
subterranean
formation, by the one or more flow control valves, provides a flowpath for
conducting of
formation fluid from the subterranean formation to the production tubular 30.
[0058] In some embodiments, for example, the one or more flow control
devices are
integrated within the wellbore tubular 20. For those embodiments where the one
or more
flow control devices are provided by the wellbore tubular, in some of these
embodiments,
for example, the wellbore treatment tubular includes a tool for selectively
effecting
opening and closing of the one or more flow control devices integrated within
the wellbore
tubular for effecting fluid communication between a selected zone of the
subterranean
formation 50 and the wellbore treatment tubular, and thereby facilitating the
delivery of the
wellbore treatment fluid to the selected zone of the subterranean formation 50
to effect
treatment of the selected zone of the subterranean formation, independently of
other zones
of the subterranean formation. Also for those embodiments where the one or
more flow
control devices are provided by the wellbore tubular, in some of these
embodiments, for
example, the production tubular 30 includes a tool for selectively effecting
opening and
closing of the one or more flow control devices integrated within the wellbore
tubular for
effecting fluid communication between a selected zone of the treated
subterranean
formation 50 and the formation fluid-receiving fluid passage portion 3231 of
the
production tubular 30, while isolating other ones of the zones of the treated
subterranean
formation, and thereby facilitating flow of the formation fluid from the
selected zone of the
treated subterranean formation, to the formation fluid-receiving fluid passage
portion 3231,
while isolating other ones of the zones of the treated subterranean formation
from the
formation fluid being flowed from the selected zone.
[0059] The flow control devices may comprise sliding sleeves, valves, and
other types
of flow control devices which may be actuated by a member dropped down through
the
associated tubular.
[0060] In the above description, for purposes of explanation, numerous
details are set
forth in order to provide a thorough understanding of the present disclosure.
However, it
26
CA 02827459 2013-09-17
will be apparent to one skilled in the art that these specific details are not
required in order
to practice the present disclosure. Although certain dimensions and materials
are described
for implementing the disclosed example embodiments, other suitable dimensions
and/or
materials may be used within the scope of this disclosure. All such
modifications and
variations, including all suitable current and future changes in technology,
are believed to
be within the sphere and scope of the present disclosure. All references
mentioned are
hereby incorporated by reference in their entirety.
27
